This invention is related to the thermal management of power supplies to high performance data processors, such as the PENTIUM processors sold by Intel Corp.
Modern high performance data processors such as the PENTIUM processors sold by Intel Corp. are high transistor count integrated circuit devices that can operate at processor core (also referred to as chip core) clock frequencies of 1 GHz and higher. Due to their high transistor count and high clock frequencies, these types of data processors consume a significant amount of power relative to the other components of the computer system, particularly in a mobile computer system such as a laptop/notebook computer. Many computer system architectures now include a separate, processor power supply that regulates the chip core voltage and delivers the large amount of power demanded by the high performance processor. In some cases, the processor power supply also powers integrated circuit (i.e., IC) devices that are in communication with the processor, such as the system chipset. The processor power supply is typically installed directly on the main printed wiring board (sometimes referred to as a motherboard), adjacent the processor IC package.
The processor power supply may include a number of components that cooperate to provide a regulated, DC voltage, at a specified maximum load current, to the processor. A power inductor (sometimes referred to as a xe2x80x98buckxe2x80x99 inductor if a buck-type switching regulator controller is used) and a filter capacitor are provided to smooth out a number of switching currents that are fed to them, and thereby provide a substantially DC load current to the processor. Switching power devices (such as metal oxide semiconductor field effect transistors, i.e. MOSFETs) channel the load current from a typically unregulated source, such as the main power supply of the computer system which may include a battery in the case of a mobile system. A switching regulator controller, such as a buck controller, receives feedback from the load and other points in the processor power supply, and in response provides the needed control signals to the switching power devices so that the load continuously receives the regulated, DC voltage under a wide range of load current. A driver circuit is often included, between the regulator controller and the power devices, to more effectively drive the gates of switching power FETs or drive other control electrodes of the switching power devices.
The design of the processor power supply is constrained by several factors. First, the power supply should reliably deliver the peak power (i.e., the regulated DC voltage multiplied by the peak current) expected to be used by the processor. For instance, a conventional, 1.2 GHz MOBILE PENTIUM III processor may demand 18 Amperes at a chip core voltage of 1.1 Volts, which is approximately 20 Watts of power. In general, to increase the reliability of a power supply, the size of the power delivery components (for example the inductor and the switching power devices) may need to be increased for handling higher power levels. This, however, can conflict with another constraint, namely that the power supply should be physically small enough to fit inside the computer system package. The conflict is particularly apparent when designing for a high performance notebook computer, because such a system demands a high peak power level from the processor power supply but allows only a relatively small physical space in which to house it.